by Gunnar Moller and Stephen Stretton
There is an overwhelming scientific consensus that the earth’s atmosphere is warming up due to the release into the atmosphere of carbon dioxide and other greenhouse gases due to human activity. The atmospheric level of carbon dioxide is now far higher than any time in the last 400 thousand years (the last 4 ice age cycles). So far, the global temperature has risen by about 0.5C against the long run average. Over the next 100 years, global temperature is likely to increase by a further 1.5 to 6C (according to the UN panel the IPCC, although the UK’s Tyndall centre believes their is a potential for even higher rises of 8C, if positive feedback is taken into account).
Such climate changes will have widespread effects across the earth.
- There will be increased frequency of heat waves and droughts in already hot or dry areas. This may precipitate famine and conflict over scarce water supplies.
- Hurricanes and other violent weather will increase in intensity. The 2005 Hurricane season was the most destructive on record with the greatest number of storms ever recorded.
- Large parts of marginal semi-desert will turn into desert. In particular, much of the area directly south of the Sahara will be swallowed by the desert. Much of the Mediterranean (Spain, Italy, Greece) may become desert.
- Sea levels will rise. Whilst this is a fairly slow process, once one of the various polar ice sheets starts to melt, it is difficult to arrest the process, since sea/rock absorbs more solar energy than white ice. The melting of the Greenland or west Antarctic ice sheets would each raise the sea level by 6.5m each (13m in total), drowning many islands and costal towns. If the East Antarctic ice sheet melted, the rise would be 84m. Melting in the ice sheets has recently accelerated.
- The flow of cold melt water from the Arctic may interrupt the ‘gulf stream’ part of the heat conveyor that transports energy from the tropics to temperate areas. This will cause Europe and in particular NorthWest Europe to become locally much colder (perhaps 5C), and maybe to have a climate more similar to Newfoundland, Canada.
- Tropical regions such as West Africa may become even warmer. In the last few months there has been evidence that the flow of the Gulf Stream may be as much as 30% less than previously.
- There will be widespread changes in ecosystems including the collapse of the coral reefs (probably inevitable even with moderate climate change).
- Increased disease frequency as e.g. malaria spreads to other areas.
A complex physical system such as the earth’s climate contains both negative and positive feedbacks. For small perturbations, negative feedback effects may dominate; otherwise the system would not persist at this point. However, such systems may have a ‘tipping point’ past which the positive feedback effects may overwhelm the negative feedback loops.
Various potential positive feedback systems have been identified for the earth. For example:
- The melting of ice leads to a change in the colour of the earth’s surface from a reflective white, to black, which absorbs more heat.
- Global warming may cause the collapse of rainforest ecosystems already ravaged by deforestation, releasing much stored CO2.
- There are huge stores of Methane (a greenhouse gas) Siberia in permafrost. This permafrost may melt. (Recently scientists have seen that this may have started to happen).
- Whilst moderate climate change (e.g. 1C) therefore may be counteracted by various natural systems, large climate change (>2C) may well be dangerous. It is clear that humans need to avoid highly polluting behaviour until and unless it is known with certainty that these effects are safe. If anything, the scientific evidence at present points to the reality of many of the proposed changes.
Human activity takes time to adjust. We need to change our methods of transport and energy production so that we emit far less CO2.
It has been estimated that the sustainable level of energy consumption is about 20% of average UK consumption and about 10% of average US consumption. This can be accomplished using a ‘personal energy quota’. (The centre for alternative technology www.cat.org.uk has further info). In particular, we need to insulate our houses well, avoid low occupancy car use, dress up warmly rather than relying excessively on heating, and particularly avoid unnecessary air travel. (E.g. see www.raileurope.co.uk). In fact, this is merely a reversal to habits of a decade or two ago, where people were not noticeably less content than they are today. The author has adopted such a ‘sustainable Carbon Dioxide quota’ without much trouble. It takes a little time to adapt habits but it is not difficult to do. Those with international jobs courses, or families would have twice the usual quota (to allow for the possibility of one intercontinental flight per person per year).
We need to lobby our governments to produce energy through methods that produce little or any carbon dioxide. For example in the UK, and the other major economies with pre-existing nuclear industries (US, Canada, Europe, Japan, Russia, India and China) the ‘baseload’ energy (75% of total) that is needed 24 hours a day can be produced by nuclear energy, as a ‘stopgap’ until renewable energy or fusion power is available. (Economical, technically advanced, efficient and safe. Arguably it is safer to have a well-funded nuclear industry with new and safe reactors rather than to have many demoralised and unemployed nuclear scientists, with poorly funded and/or derelict nuclear facilities. Nuclear reactors design has improved massively over the last decades). Wind power can be used in UK (but requires some backup for when the wind isn’t blowing such as pumped storage hydro plants). Solar energy can be harnessed in other countries without pre-existing nuclear infrastructure. Once energy production is non-CO2 emitting, cars can be converted to being run from electricity, further cutting emissions.
Finally, we need to lobby our governments (particularly in the US but globally as well) to support treaties that cut carbon dioxide emission. The European Union has pioneered an emissions trading scheme which caps total emissions and then charges for permits to emit carbon dioxide. Since low carbon technologies are immature – they can still be improved, (whereas polluting technologies have little scope for improvement)- it may be that action to change energy and transport systems will pay for itself by increasing the economy’s productive capacity.
The government wants to get our emissions down to from 10 to 4 tonnes
of CO2 per person per year. But 4 tonnes CO2 per person per year is
the CURRENT global average of CO2 from fossil fuel alone…
Where the UK hopes to be in 2050, even if adopted by everyone, would
not reduce global emissions (and certainly not get them to a safe
To keep global warming below 2 degrees, We need 1 tonne per person per
year (by 2030 if possible, but certainly before 2050). (See “how much
CO2 can we emit” attachment)
Anything above 2 degrees and we hit tipping points and we have a mass
extinction event (of plants, animals and the poor). (See “Six degrees
*We need a national campaign for 1 tonne per person per year, a 90% reduction on 1990 levels.
This can be achieved while maintaining a healthy and vibrant low-carbon economy.
A guaranteed minimum electricity price (indexed and time-averaged over each 5 year period, for the design life of each project) for long-term investors in carbon free (<50gCO2/kWh) electricity generation capacity.
By Tim Joslin
Full Article (pdf)
The threat of global warming has led governments around the world to encourage the use of biofuel, in particular in the transport sector, in the hope of displacing fossil fuel. The UK, following an EU Biofuels Directive, is introducing a Road Transport Fuel Obligation (RTFO), requiring fuel providers to ensure that 5% of their total road transport fuel sales “is made up of fuels from renewable sources” by 2010.
It is already well-known, through the efforts of, in particular, George Monbiot, that a large-scale diversion of agricultural land to the production of biofuel will set up competition between food and fuel, between people and cars. Vast tracts of rainforest are already being cleared to create more land on which to grow biofuel crops, such as oil palm. Governments may argue that they can manage these problems, whilst continuing to promote biofuel use. This is doubtful.
But there are even more fundamental arguments against biofuels. This paper shows that the use of biofuel to supplement fossil fuel for vehicle transport is not only disastrous in practice, it is also flawed even on its own terms, in two distinct ways:
- plant-growth on land is one of the main ways in which CO2 is removed from the atmosphere. Land is therefore a resource in the fight against global-warming. Even under optimistic assumptions, growing biofuel crops will not reduce atmospheric levels of CO2 over any timescale of up to more than a century, compared to preventing deforestation or even simply leaving already cleared land alone and allowing natural plant growth to capture carbon.
- we know that within a few decades we must dramatically reduce our reliance on fossil-fuels, especially in the transport sector, where capturing and sequestering carbon emissions would be very expensive. In terms of achieving this objective, the use of biofuel is counter-productive. Instead of encouraging investment in energy supplies that are renewable for the long-term, measures such as the RTFO incentivise businesses and individuals to make further investments in technology for burning fossil fuels. Government should instead encourage a technological path from hybrid cars, through plug-in hybrids, to electric cars. Instead of continuing to burn carbon, our future transport energy needs can be met by the generation of electricity using true renewable and/or nuclear technologies.
Biofuels are not the answer.
The investment required to decarbonise the energy system (for the UK, about £10billion per year for 25 years) can help to provide for the retirement of the baby boomer generation. By guaranteeing future electricity prices, private sector investment can provide energy security and avoid war. We can eliminate taxes on working families and business investment and instead penalise coal, crude oil, and gas as they enter the country.